As the number of wireless protocols supported by wireless communication devices increases, the issue of wireless signal interference becomes more and more prevalent. Many of these wireless standards operate at frequencies located nearby one another. For example, 4G wide area network technologies such as IEEE 802.16e wireless metropolitan area network communications (sometimes referred to as WiMAX) and 3GPP Long Term Evolution (LTE) operate in the 2.6 GHz frequency band while IEEE 802.11b/g wireless local area network communications (sometimes referred to as WiFi), and IEEE 802.15 wireless personal area network communications (sometimes referred to as Bluetooth) operate in the 2.4 GHz ISM band.
Due to the close physical proximity of transceivers for each technology on a mobile device, such as a dual-mode WiMAX/CDMA cellular phone with Bluetooth, transmissions to or from one transceiver can cause upwards of 58% packet loss for the other transceiver in certain situations. This happens most noticeably when one transceiver is transmitting while the other transceiver is set to receive. For example, a signal transmitted by a WiMAX transceiver in such a dual-mode phone overpowers the co-located Bluetooth receiver with what is interpreted as noise.
Co-existence refers to the ability to operate two wireless technologies, such as WiMAX and Bluetooth, simultaneously on the same device without significant degradation to either's operation. Co-existence solutions should not rely upon synchronization of the clocks for each technology, so that energy appears to be spread randomly through the ISM band and does not coordinate with licensed bands. This creates an opportunity to develop efficient methods for reducing co-existence types of interference while staying within the constraints put in place for the ISM frequency band.
Some methods created to deal with this co-existence problem rely upon access to the inner workings of both transceivers' integrated circuits. These types of solutions require using chips from the same manufacturer in order to lessen the impact of co-existence interference. Those types of solutions, however, present a problem in that they force purchasers to use chips from the same manufacturer in order to alleviate at least some of the interference. Thus, there is an opportunity to develop a solution that promotes co-existence irrespective of transceiver chip manufacturers.